Sen. Menendez: US, NATO Should Arm Ukraine

The United States "should provide the Ukrainians with the type of defensive weapons that will impose a cost" upon Russian President Vladimir Putin, Senate Foreign Relations Committee Chairman Robert Menendez, speaking from a fact-finding mission in Ukraine, said Sunday.

"Thousands of Russian troops are here with tanks, missiles, heavy artillery and are directly engaged in what is clearly an invasion," the New Jersey Democrat told CNN "State of the Union" host Candy Crowley Sunday. "This is a watershed moment."

Menendez told Crowley that he believes Putin has sized up his potential western opposition, and came to the conclusion that the most difficult sanctions and arms necessary for the Ukrainians to defend themselves are not coming.

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"We have to prove him wrong," he said. "We have to look at sectoral sanctions, whether in the financial services, defense or energy ... we should provide the Ukrainians with the type of defensive weapons that will impose a cost upon Putin for further aggression."

President Barack Obama has said that the Ukrainian situation will not be solved through military force, but Menendez said that was just an initial assessment and this week's invasion means circumstances have changed.

"There are those in Europe and elsewhere who say we don't want to provoke Putin," he said. "Putin doesn't need provocation. In this case, weakness is a greater provocation for Putin to strike."

There are two things Putin understands, said Menendez: Strength and the costs to Russians.

"Hopefully the European Union will move with us into more significant sectoral sanctions," said Menendez. The costs to Russians will also come if Ukraine sends "their sons and daughters back in body bags to Russia, and Russian mothers say 'what is happening here?' "

The Ukrainians are "more than willing to fight," said Menendez, and have shown a great deal of restraint.

"But it's at a point where Russia has come, invaded with thousands of troops, with missiles, with tanks," he told Crowley. "This is no longer the question of some rebel separatists, this is a direct invasion by Russia. We must recognize it as that...it's not rebels; it's Russian soldiers.

The question of providing lethal weaponry to Ukraine "may very well be on the table again" with the changed circumstances, said Menendez.

"Look, Russia [has] violated the international order that we had invited it to since the Cold War," said Menendez. "The whole effort was to get Russia and other countries to observe that you don't solve disputes by invading another country, taking over their territory, and annexing them, and Russia has violated that."

Menendez said that from his perspective, Putin is waging a war against Europe, but it is being fought on Ukrainian territory.

"Everything that he despises about Europe is what he's concerned about Ukraine moving toward," said Menendez. "At the end of the day this is also about our concerns globally."

Menendez said he's not suggesting putting U.S. or NATO troops on the ground in Ukraine, but "we have to give the Ukrainians the fighting chance to defend themselves."